Fast opinions come and go. Here are the slow facts.

Spare Me the Climate Change

My neighbor says the earth’s climate is changing because we use too many fossil fuels. I spent a few minutes asking simple questions to see if I agree or not. His argument goes like this-

Earth’s climate is changing, andClimate change is caused by increased levels of atmospheric Carbon Dioxide, andThe increase in CO2 is caused by man using fossil fuels, soGovernments need to regulate our use of fossil fuels to stop climate change because..Climate change is bad for us.

Hmm. Really? Let’s look at that one piece at a time

Yes, earth’s climate is changing

Looking at the data, the temperature of the earth changes a lot. In fact, change appears to be the only constant. We are supposed to ignore the “good” climate change that brought the earth to the average global temperatures of the mid 1800 when things were “perfect”. “Perfect” means before the industrial revolution. It turns out we needed plenty of climate change to get to “perfect”. The world was hotter 3 million years ago than it is now. If we go back 1 million years, then the world was cooler than it is now; a lot colder. Think wooly rhinoceros in Spain kind of colder, and kiss your sangria good bye.

It was unusually warm during the medieval warm period (950 to 1250AD), and colder in the little ice (1550 to 1850 AD) age than it is today. That means we’ve seen change of this magnitude and human industry did not cause one bit of it. For the last million years the earth has been in and out of a ice ages. Our current warm period that started 12 thousand years ago is the exception, not the rule. It is certainly not the average temperature. If climate change is bad, then I’m way confused by all this natural variability.

Look at the data. It isn’t strange that the climate changes; it would be uncharacteristic if the climate was constant. From Wikipedia-

The climate certainly isn’t steady. What could have changed the earth’s climate before 1800 AD and the industrial revolution?

Here comes the sun-

We assume the sun is constant because it looks the same from day to day. Claiming the sun is constant and has been constant is really a matter of faith, not science. It turns out that we have evidence of the sun’s instability. The amount of nitrogen converted to carbon 14 is modulated by the solar wind. This graph shows the variability of carbon 14 found in ice cores. The sun is inconsistent even over the short period of recorded history.

What of the earth itself?

The eccentricity of earth’s orbit changes with time. The earth’s inclination (obliquity) changes with time. The phase (precession) of the seasons with eccentricity changes over hundreds of thousands of years. Called Milankovitch cycles, these cycles slightly change solar heating and the warmth of each season. Slight increases in solar insolation have a particularly strong effect on temperature at the end of each glacial period. I know that the earth’s magnetic field has changed with time, but I don’t know how this might affect average temperatures at the surface of the earth. Welcome to the ever-changing earth. From Wikipedia-

We’ve seen that average global temperature is anything but constant. Taken together, this is a strong hint that all climate change might not be from man made causes. Let’s keep looking.

What are greenhouse gasses and does each gas act the same way? Greenhouse gasses reflect infrared radiation. That means they reflect the heat radiation emitted by the earth out into space. They also reflect some of the heat radiation that comes from the sun. In combination, greenhouse gasses both heat and moderate our climate. The principal greenhouse gasses are- water vapor, carbon dioxide, methane and ozone. They are not equally effective per molecule, and the concentrations of gasses are not equal in our atmosphere. The potency and concentration are combined to form a contribution from each gas. Note that the contributions of each gas are far from equal.

Note that the largest contributor by far is water vapor. All other contributions combined are 20 times less significant. That is important. Carbon dioxide isn’t an important player in our current climate. I wonder why the newspapers and press don’t tell us about that. Don’t you?

The increase in CO2 is caused by man using fossil fuels

How much CO2 is manmade? I’m glad you asked, because THAT is the next critical question. Carbon moves through our ecosystem by the ton. The numbers in this picture are in BILLIONS of tons. About 1600 billion tons of carbon enter and leave the atmosphere each year. Humans emit 29 billion tons that weren’t emitted two hundred years ago. From http://www.skepticalscience.com/human-co2-smaller-than-natural-emissions.htm

We also absorb some carbon and remove it from the biosphere. You probably live in such a carbon sink. Again, I took this table from http://www.geocraft.com/WVFossils/ice_ages.html#anchor2108263 by Monte Hieb. I encourage you to read it. The table shows that we do emit carbon into the environment, and the amount we emit forms about one ninth of one percent of the greenhouse gasses. Is that significant?

So, yes, CO2 is increasing. It will add some amount to global temperature. The science is far from settled about how much and the importance of that change.

Governments need to regulate our use of fossil fuels to stop climate change because climate change is bad.

I can cobble some numbers together to justify the theory of climate change. When I look at the data, I can not convince myself that there is a danger from man made climate change. I think there is an ideology at work here more than a science. Does that surprise anyone?

One group wants more control. The only thing new about the desire for control is that the popular justification changes with time. While it is still permitted, please allow me to disagree with man made climate change..

P. S.: I found an excellent paper that says it better than I could. Look here.
`-`-`-

Please rate, share or comment. I will ask you to speak for yourself rather than use someone else’s words and ideas.